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Ground-based heterodyne spectroscopy is used to observe the night side of Venus by probing single pressure broadened CO2 absorption lines. From the pressure induced line broadening, the predominant temperature at different altitude layers can be deduced. It is found, that heterodyne spectroscopy is sensitive to probe the mesosphere between similar to 60 km and 90 km with an altitude resolution of similar to 4.5 km. During two observing campaigns in March and May 2012, four different locations on the planet were investigated. Herein, we report on the retrieval of vertical temperature profiles in the nightside atmosphere of Venus. Retrieval of atmospheric parameters is based on a Levenberg-Marguard chi(2) optimization that iteratively compares observed data to telluric transmittance corrected Venus' top-of-atmosphere spectra calculated using a radiative transfer algorithm. The deduced profiles are compared to the Venus International Reference Atmosphere and some found to be in satisfactory agreement. Sub-Doppler resolution Infrared heterodyne observations can provide temperature measurements that complement existing sub-mm and space based observations. (C) 2015 Elsevier Ltd. All rights reserved.

Ground-based heterodyne spectroscopy is used to observe the night side of Venus by probing single pressure broadened CO2 absorption lines. From the pressure induced line broadening, the predominant temperature at different altitude layers can be deduced. It is found, that heterodyne spectroscopy is sensitive to probe the mesosphere between similar to 60 km and 90 km with an altitude resolution of similar to 4.5 km. During two observing campaigns in March and May 2012, four different locations on the planet were investigated. Herein, we report on the retrieval of vertical temperature profiles in the nightside atmosphere of Venus. Retrieval of atmospheric parameters is based on a Levenberg-Marguard chi(2) optimization that iteratively compares observed data to telluric transmittance corrected Venus' top-of-atmosphere spectra calculated using a radiative transfer algorithm. The deduced profiles are compared to the Venus International Reference Atmosphere and some found to be in satisfactory agreement. Sub-Doppler resolution Infrared heterodyne observations can provide temperature measurements that complement existing sub-mm and space based observations. (C) 2015 Elsevier Ltd. All rights reserved.

The Cassini Huygens mission provides a unique opportunity to combine ground-based and spacecraft investigations to increase our understanding of chemical and dynamical processes in Titan s atmosphere Spectroscopic measurements from both vantage points enable retrieving global wind structure temperature structure and atmospheric composition An updated analysis of Titan data obtained with the NASA Goddard Space Flight Center s Infrared Heterodyne Spectrometer (IRHS) and Heterodyne Instrument for Planetary Wind and Composition (HIPWAC) prior to and during the Cassini Huygens mission is compared to retrievals from measurements with the Cassini Composite Infrared Spectrometer (CIRS) IRHS/HIPWAC results include the first direct stratospheric wind measurements on Titan constraints on stratospheric temperature and the study of atmospheric molecular composition These results are compared to CIRS retrievals of wind and temperature profile from thermal mapping data and ethane abundance at 10-15 degrees South latitude near the equatorial region IRHS/HIPWAC wind results are combined with other direct techniques stellar occultation measurements and CIRS results to explore seasonal variability over nearly one Titan year and to provide an empirical altitude profile of stratospheric winds varying from similar to 50 to 210 m/s prograde The advantage of fully resolved line spectra in species abundance measurements is illustrated by comparing the possible effect on retrieved ethane abundance by blended spectral features of other molecular constituents e g acetylene (C2H2) ethylene (C2H4) allene (C3H4) and propane (C3H8) which overlap the nu(9) band of ethane and are not resolved at lower spectral resolution IR heterodyne spectral resolution can discriminate weak spectral features that overlap the nu(9) band of ethane enabling ethane lines alone to be used to retrieve abundance Titan s stratospheric mean ethane mole fraction (8 6+/-3 ppmv) retrieved from IRHS/HIPWAC emission line profil

The Cassini Huygens mission provides a unique opportunity to combine ground-based and spacecraft investigations to increase our understanding of chemical and dynamical processes in Titan s atmosphere Spectroscopic measurements from both vantage points enable retrieving global wind structure temperature structure and atmospheric composition An updated analysis of Titan data obtained with the NASA Goddard Space Flight Center s Infrared Heterodyne Spectrometer (IRHS) and Heterodyne Instrument for Planetary Wind and Composition (HIPWAC) prior to and during the Cassini Huygens mission is compared to retrievals from measurements with the Cassini Composite Infrared Spectrometer (CIRS) IRHS/HIPWAC results include the first direct stratospheric wind measurements on Titan constraints on stratospheric temperature and the study of atmospheric molecular composition These results are compared to CIRS retrievals of wind and temperature profile from thermal mapping data and ethane abundance at 10-15 degrees South latitude near the equatorial region IRHS/HIPWAC wind results are combined with other direct techniques stellar occultation measurements and CIRS results to explore seasonal variability over nearly one Titan year and to provide an empirical altitude profile of stratospheric winds varying from similar to 50 to 210 m/s prograde The advantage of fully resolved line spectra in species abundance measurements is illustrated by comparing the possible effect on retrieved ethane abundance by blended spectral features of other molecular constituents e g acetylene (C2H2) ethylene (C2H4) allene (C3H4) and propane (C3H8) which overlap the nu(9) band of ethane and are not resolved at lower spectral resolution IR heterodyne spectral resolution can discriminate weak spectral features that overlap the nu(9) band of ethane enabling ethane lines alone to be used to retrieve abundance Titan s stratospheric mean ethane mole fraction (8 6+/-3 ppmv) retrieved from IRHS/HIPWAC emission line profil

The authors report on an InP based photovoltaic quantum cascade detector operating at 16.5 µm and using miniband-based vertical transport. This concept allowed the construction of a longitudinal optical phonon extraction stair with two rungs without touching on a high device resistance. At 10 K, they observed a responsivity of 1.72 mA/W and a Johnson noise limited detectivity of 2.2×109 Jones. Altogether, this design resulted in detection at temperatures of up to 90 K with a lower bandwidth limit of 200 MHz imposed by the measurement setup.

Quantum cascade (QC) structures, for both emitting and detecting mid-infrared radiation, are powerful devices for spectroscopy. QC lasers (QCLs), which have been built for nearly 15 years, already play the leading role in certain wavelength regions. QC detectors (QCDs) are a fairly new development, which has been evolving from the QCL research. In high-resolution heterodyne spectrometers for astronomy, such as the Cologne tuneable heterodyne infrared spectrometer (THIS), QC devices help to open new windows to space as discussed in this paper. We will briefly review the use of QC devices in THIS, show recent results in measuring planetary atmospheric dynamics and give an outlook to astronomical goals for the future.

Quantum cascade (QC) structures, for both emitting and detecting mid-infrared radiation, are powerful devices for spectroscopy. QC lasers (QCLs), which have been built for nearly 15 years, already play the leading role in certain wavelength regions. QC detectors (QCDs) are a fairly new development, which has been evolving from the QCL research. In high-resolution heterodyne spectrometers for astronomy, such as the Cologne tuneable heterodyne infrared spectrometer (THIS), QC devices help to open new windows to space as discussed in this paper. We will briefly review the use of QC devices in THIS, show recent results in measuring planetary atmospheric dynamics and give an outlook to astronomical goals for the future.

The authors report on an InP based photovoltaic quantum cascade detector operating at 16.5 µm and using miniband-based vertical transport. This concept allowed the construction of a longitudinal optical phonon extraction stair with two rungs without touching on a high device resistance. At 10 K, they observed a responsivity of 1.72 mA/W and a Johnson noise limited detectivity of 2.2×109 Jones. Altogether, this design resulted in detection at temperatures of up to 90 K with a lower bandwidth limit of 200 MHz imposed by the measurement setup.